Synthesis of cobalt doped ZnO/reduced graphene oxide nanorods as active material for heavy metal ions sensor and antibacterial activity

Cobalt doped ZnO/reduced graphene oxide (Co:ZnO/RGO) nanorods were synthesized by a chemical co-precipitation method. The morphological and physical properties were analyzed by High Resolution Scanning Electron Microscope (HR-SEM), Transmittance Electron Microscope (TEM), Fourier Transform Infra-Red spectroscopy (FTIR), X-Ray Diffraction (XRD) and UV–VIS NIR spectroscopy (UV–VIS NIR). The catalytic activity of synthesized nanostructure toward Cd (II) and Pb (II) ions oxidation was investigated by the electrochemical techniques and Co:ZnO/RGO nanorods exhibited an excellent electrocatalytic oxidation of Cd (II) and Pb (II) ions. Difference Pulse Voltammetry (DPV) studies shown that the fabricated electrode had excellent sensitivity for Cd (II) and Pb (II) ions with the detection limit of 0.94 μg/L (Cd (II)) and 0.83 μg/L (Pb (II)) over a concentration range of 10–90 μg/L. Finally, the antibacterial activity test towards the gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) showed that the Co:ZnO/RGO nanorods have better antibacterial activity compared to ZnO/RGO. [Display omitted] •The Co:ZnO/RGO nanorods were synthesized by a chemical precipitation routes.•The Co:ZnO/RGO nanorods were clearly observed by SEM and TEM images.•The prominent shift in the FTIR and UV spectra were clearly indicated the formation of Co:ZnO/RGO nanorods.•Catalytic activity of Co:ZnO/RGO nanorods were utilized to detect heavy metal ions.•The Co:ZnO/RGO nanorods had superior antibacterial performance.